The invention relates to a probe head, used for example, to orientate a probe relative to a quill of a coordinate measuring machine.
1. Description of Prior Art
It is known to provide a motorised probe head having a support for mounting the probe head to the quill of a coordinate measuring machine, a first rotor mounted to and for rotation relative to the support, and a second rotor mounted to and for rotation relative to the first rotor. The second rotor carries a connector for connecting a workpiece-sensing probe to the probe head. To move the probe head from one relative orientation to another, position demand data is programmed into a suitable micro processor, and instructions are sent to the motors of the probe head. This enables the probe to be orientated in any desired direction, to facilitate measurements of complex-shaped workpieces.
2. Summary of the Invention
The present invention provides a manually operable probe head, having a support, a rotor mounted to, and for rotation relative to the support about an axis, the rotor being mounted for seating in, and rotation between a plurality of rest locations, and an indicating mechanism provided on the probe head for storing data corresponding to a predetermined position of the rotor relative to the support and for displaying when the rotor is in said predetermined position.
In one preferred embodiment of the present invention the means for storing data and the signalling means may be respectively provided by a markable scale on one of said rotor and support, and a reference mark adjacent the scale on the other of said rotor and support.
The indicating mechanism preferably also further comprises means provided on the probe head for generating signals, each signal corresponding to a unique position of the rotor relative to the support, and means for displaying on the probe head an instantaneous position of the rotor relative to the support.
Preferably, the indicating mechanism further comprises a memory for storing at least one of said signals corresponding to a said predetermined position, and means for indicating coincidence between a signal stored in the memory and a signal from the signal generator.
The indicating means also preferably further comprises means for generating from said signals an instruction for moving the rotor from a position other than a said predetermined position, to a said predetermined position, and for displaying the said instruction on the probe head.
A second preferred embodiment of indicating mechanism provides a markable scale provided on one of the rotor and support and a reference mark adjacent the other of said rotor and support.